The present invention relates to the field of fitted bed sheets. In particular, the present invention relates to certain improvements In fitted sheets.

The present applicant is the inventor of the fitted bed sheet described and claimed in US-A-5,765,241 (corresponding to EP-A-787 451). That sheet, which is fabricated from knit material, is known in the trade as an envelope sheet. It is made from a tube of knit fabric, slit along an edge to form a rectangle, The side margins of the rectangle are then folded inwardly to the midline of the sheet, and top and bottom edges are sewn, joining the top and bottom edges of the folded-over margins to the top and bottom edges of the sheet of fabric. The inwardly directed edges of the margins are then finished with binding in a continuous loop to finish the sheet. The advantages of such a sheet are that it is economical to manufacture, and it fits securely on a mattress, especially a multi-position hospital mattress, without coming off. It lays flat on the mattress, even when the mattress is articulated, which results in a comfortable surface that does not have wrinkles on it to promote bed sores.

The applicant has identified an area of potential improvement in the envelope sheet. The sewing of the top and bottom edges of the folded-over sheet is substantially transverse to the longitudinal axis of the sheet. This does tend to create "ears" of material at the outer edge of the sheet when it is placed on a mattress. These ears tend to be positioned on the side surface of a mattress, near the comers of same. They are untidy looking, and a waste of material. That is, they create the appearance of an ill-fitting sheet

In a broad aspect, then, the present Invention relates to a fitted sheet for a mattress comprising a rectangular panel of knit material having a central rectangular area extending from one end of said panel to the other end thereof, and side margins flanking said central area, said side margins being folded under said central area and joined thereto by seams extending across each end of said central rectangular area, characterized in that said seams at each end of said central rectangular area are arcuate or angled from the center.

In drawings that illustrate the present invention by way of example:

• Figure 1 is a plan view of a first embodiment of the present Invention;
• Figure 1A is an alternative embodiment of the sheet of Figure 1.

Referring now to Figure 1, a sheet 1 is illustrated. It comprises a central panel 2 with margins 3 folded over onto same, As shown in dotted lines, the top edge 4 and bottom edge 5, in a sheet according to known envelope sheet design, are sewn across in transverse lines. These edges may have binding attached for additional strength, if desired. When applied to a mattress, the comers 6 at the ends of the top 4 and bottom edges of the sheet tend to form ears.

The applicant eliminates the formation of ears in the comers 6 of the envelope sheet 1 byproviding arcuate 8 rather than straight end edges, as illustrated. By arcing - or even simply angling from the centre (see Figure 1a, lines 81) - the end edges, the formation of ears of fabric in each comer of the sheet is eliminated or substantially reduced.

Referring to Figure 1, the present invention also provides, in a preferred embodiment, a loop 14 or a flap of tape, binding, or cloth, extending from the upper seam 8. The function of the feature is to provide a resilient surface to which an alarm or intercom bell may be attached without damaging the knit fabric of the sheet.